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1.
We report here the accumulation of p-hydroxybenzoic acid in Agrobacterium rhizogenes-induced hairy root cultures of Daucus carota. This phenolic acid finds application in food, pharmaceutical and polymer industries. Metabolic profiling of phenolics by HPLC/ESI-MS from these hairy roots showed a considerable amount of p-hydroxybenzoic acid accumulation both in cytosol and in the cell wall. Analyses of HCl and NaOH treated soluble phenolic fractions resulted in the elution of peaks with same retention time and similar UV-absorption spectra as observed with p-hydroxybenzoic acid standard. This suggests that p-hydroxybenzoic acid is present in the cytosol as free-form (unconjugated). A correlation has been drawn between the accumulation of soluble and wall-bound phenolic acids on a time-course basis. An apparent absence of any p-hydroxybenzoic acid-glucoside supports this observation, which in turn encourages the idea of its incorporation in the cell wall in an alkaline-labile form. 相似文献
2.
Shashwati?Ghosh Ashish?Sachan Adinpunya?MitraEmail author 《World journal of microbiology & biotechnology》2005,21(3):385-388
Summary A ubiquitous white rot fungus Schizophyllum commune was used for the first time to study the degradation of ferulic acid. Vanillic acid was observed as one of the major products of ferulic acid catabolism, with vanillin formed as an intermediate. Almost 99.9% ferulic acid with a initial concentration of 5 mM was consumed by this fungus after 16 days of incubation at 37 °C. 相似文献
3.
The fragrant rootstocks of Hemidesmus indicus are known to accumulate 2-hydroxy-4-methoxybenzaldehyde (MBALD), yet, the enzymatic route to this hydroxybenzoate is not known. Therefore, root organs of H. indicus hold promises to unravel the biosynthesis related to this phenolic fragrance. Chitosan treatment at 200mg/L concentration to the excised roots effectively increased phenolic accumulation in both the cortex and cork tissues reaching a peak after 24h treatment and decreasing thereafter. The activity of phenylalanine ammonia-lyase (PAL) enzyme in excised roots also increased upon chitosan elicitation, and the maximum specific activity was recorded after 12h of elicitation. Suppression of PAL in vivo by using a specific irreversible inhibitor aminooxyacetic acid (AOAA) resulted in the decrease in MBALD content, indicating its formation via phenylpropanoid pathway. 相似文献
4.
In this study, methyl jasmonate (MJ)-elicited hairy root cultures of Daucus carota were explored to study the enzymatic route to p-hydroxybenzoic acid (p-HBA) biosynthesis. Treatment with 100muM MJ caused an enhanced accumulation of p-HBA as well as total phenolic content in elicited root lines as compared to untreated (controls) lines. Using cell-free extract as the source of crude enzymes, attempt was made to reveal the enzymatic route to p-HBA formation. The accumulation of p-HBA was preceded by a substantial upliftment of p-hydroxybenzaldehyde dehydrogenase (HBD) activity in elicited lines as compared to controls. A rapid 6-fold enhancement of phenylalanine ammonia-lyase (PAL) activity, the first enzyme of the phenylpropanoid pathway was also observed. Finally, we demonstrated here for the first time, in D. carota, the evidence of a quite unusual p-hydroxybenzaldehyde synthase (HBS)-type enzyme, which catalyzes the penultimate step of p-HBA biosynthesis by making phenylpropanoid side-chain cleavage of p-coumaric acid without involvement of any cofactor(s), but uplifted by supplementation of a thiol reagent such as DTT in the reaction buffer. This enzyme showed activity in a relatively broad pH range (7-8.4) and the temperature optimum was found to be at 34 degrees C. The MJ-treated roots showed highest HBS activity at 24h (52nkat/mg protein), which was nearly 5-fold higher than that in the control lines. 相似文献
5.
Debabrata Sircar Chiranjit Mukherjee Till Beuerle Ludger Beerhues Adinpunya Mitra 《Acta Physiologiae Plantarum》2011,33(5):2019-2024
Hairy root cultures of Daucus carota respond to methyl-jasmonate treatment with enhanced accumulation of p-hydroxybenzoic acid. The final C1-side chain of this compound is shaped by p-hydroxybenzaldehyde dehydrogenase (HBD) that catalyzes the formation of p-hydroxybenzoic acid from p-hydroxybenzaldehyde in the presence of NAD+. HBD was biochemically characterized from cell-free hairy root extracts of D. carota. The preferred substrate for HBD was p-hydroxybenzaldehyde. The apparent K
m values were 54.8 and 74.4 μM for p-hydroxybenzaldehyde and NAD+, respectively. Divalent metal cations did not significantly affect enzyme activity. 相似文献
6.
Transgenic hairy root system is important in several recalcitrant plants, where Agrobacterium tumefaciens-mediated plant transformation and generation of transgenic plants are problematic. Jute (Corchorus spp.), the major fibre crop in Indian subcontinent, is one of those recalcitrant plants where in vitro tissue culture has
provided a little success, and hence, Agrobacterium-mediated genetic transformation remains to be a challenging proposition in this crop. In the present work, a system of transgenic
hairy roots in Corchorus capsularis L. has been developed through genetic transformation by Agrobacterium rhizogenes harbouring two plasmids, i.e. the natural Ri plasmid and a recombinant binary vector derived from the disarmed Ti plasmid
of A. tumefaciens. Our findings indicate that the system is relatively easy to establish and reproducible. Molecular analysis of the independent
lines of transgenic hairy roots revealed the transfer of relevant transgenes from both the T-DNA parts into the plant genome,
indicating the co-transformation nature of the event. High level expression and activity of the gusA reporter gene advocate that the transgenic hairy root system, thus developed, could be applicable as gene expression system
in general and for root functional genomics in particular. Furthermore, these transgenic hairy roots can be used in future
as explants for plantlet regeneration to obtain stable transgenic jute plants. 相似文献
7.
Saborni Maiti Utkarsh Ravindra Moon Paramita Bera Tanmoy Samanta Adinpunya Mitra 《Acta Physiologiae Plantarum》2014,36(10):2597-2605
This study was designed to examine the chemical compositions of scent volatiles and antioxidant activities of Polianthes tuberosa L. flower extract in six different solvents. The main constituents of the volatile components were benzyl benzoate, methyl 2-amino benzoate, methyl isoeugenol, isoeugenol, benzyl salicylate, methyl salicylate, geraniol and 1,8-cineole. Total phenolic content of floral extracts in water, methanol, ethanol, ethyl acetate, hexane and dichloromethane were found to be 0.094, 0.18, 0.14, 0.007, 0.004 and 0.110 mg gallic acid equivalent/mg fresh weight, respectively. The methanol soluble fraction showed highest values of antioxidant activity through DPPH and ABTS assays. Methanol extract effectively inhibits the non site-specific DNA strand breakage caused by Fenton’s reagents. Dichloromethane and aqueous fractions also exhibited high antioxidant capacities. Aqueous extract showed highest value in FRAP assay. 相似文献
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9.
Ghosh S Sachan A Sen SK Mitra A 《Journal of industrial microbiology & biotechnology》2007,34(2):131-138
Streptomyces sannanensis MTCC 6637 was examined for its potentiality to transform ferulic acid into its corresponding hydroxybenzoate-derivatives.
Cultures of S. sannanensis when grown on minimal medium containing ferulic acid as sole carbon source, vanillic acid accumulation was observed in the
medium as the major biotransformed product along with transient formation of vanillin. A maximum amount of 400 mg/l vanillic
acid accumulation was observed, when cultures were grown on 5 mM ferulic acid at 28°C. This accumulation of vanillic acid
was found to be stable in the culture media for a long period of time, thus facilitating its recovery. Purification of vanillic
acid was achieved by gel filtration chromatography using Sephadex™ LH-20 matrix. Catabolic route of ferulic acid biotransformation
by S. sannanensis has also been demonstrated. The metabolic inhibitor experiment [by supplementation of 3,4 methylenedioxy-cinnamic acid (MDCA),
a metabolic inhibitor of phenylpropanoid enzyme 4-hydroxycinnamoyl-CoA ligase (4-CL) along with ferulic acid] suggested that
biotransformation of ferulic acid into vanillic acid mainly proceeds via CoA-dependent route. In vitro conversions of ferulic
acid to vanillin, vanillic acid and vanillin to vanillic acid were also demonstrated with cell extract of S. sannanensis. Further degradation of vanillic acid to other intermediates such as, protocatechuic acid and guaiacol was not observed,
which was also confirmed in vitro with cell extract. 相似文献
10.